Reduce string copies in GURL creation

url/gurl.cc

 // Copyright 2013 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "url/gurl.h"
 
 #include <stddef.h>
 
 #include <algorithm>
 #include <ostream>
@@ skipping 60 matching lines @@
 GURL::GURL(const GURL& other)
     : spec_(other.spec_),
       is_valid_(other.is_valid_),
       parsed_(other.parsed_) {
   if (other.inner_url_)
     inner_url_.reset(new GURL(*other.inner_url_));
   // Valid filesystem urls should always have an inner_url_.
   DCHECK(!is_valid_ || !SchemeIsFileSystem() || inner_url_);
 }
 
-GURL::GURL(const std::string& url_string) {
+GURL::GURL(base::StringPiece url_string) {
   InitCanonical(url_string, true);
 }
 
-GURL::GURL(const base::string16& url_string) {
+GURL::GURL(base::StringPiece16 url_string) {
   InitCanonical(url_string, true);
 }
 
 GURL::GURL(const std::string& url_string, RetainWhiteSpaceSelector) {
-  InitCanonical(url_string, false);
+  InitCanonical(base::StringPiece(url_string), false);
 }
 
 GURL::GURL(const char* canonical_spec,
            size_t canonical_spec_len,
            const url::Parsed& parsed,
            bool is_valid)
     : spec_(canonical_spec, canonical_spec_len),
       is_valid_(is_valid),
       parsed_(parsed) {
   InitializeFromCanonicalSpec();
 }
 
 GURL::GURL(std::string canonical_spec, const url::Parsed& parsed, bool is_valid)
     : is_valid_(is_valid),
       parsed_(parsed) {
   spec_.swap(canonical_spec);
   InitializeFromCanonicalSpec();
 }
 
 template<typename STR>
-void GURL::InitCanonical(const STR& input_spec, bool trim_path_end) {
+void GURL::InitCanonical(base::BasicStringPiece<STR> input_spec,
+                         bool trim_path_end) {
   // Reserve enough room in the output for the input, plus some extra so that
   // we have room if we have to escape a few things without reallocating.
   spec_.reserve(input_spec.size() + 32);
   url::StdStringCanonOutput output(&spec_);
   is_valid_ = url::Canonicalize(
       input_spec.data(), static_cast<int>(input_spec.length()), trim_path_end,
       NULL, &output, &parsed_);
 
   output.Complete();  // Must be done before using string.
   if (is_valid_ && SchemeIsFileSystem()) {
@@ skipping 410 matching lines @@
 void GURL::Swap(GURL* other) {
   spec_.swap(other->spec_);
   std::swap(is_valid_, other->is_valid_);
   std::swap(parsed_, other->parsed_);
   inner_url_.swap(other->inner_url_);
 }
 
 std::ostream& operator<<(std::ostream& out, const GURL& url) {
   return out << url.possibly_invalid_spec();
 }